Winter Temperatures

Preliminary data indicates that winter temperatures were far above the 30-year “normal” during the winter season. The statewide mean winter temperature of 40.8°F was 4.5°F above the 1981-2010 mean value of 36.3°F (Figure 1). This made winter 2016-2017 the 5th warmest since records began in 1895, and the second winter in a row in the top 5 warmest on record.

Winter Precipitation

The statewide mean precipitation of 7.19 inches was 2.57 inches below the 1981-2010 normal of 9.76 inches, and was the 17th driest winter season since records began in 1895 (Figure 2).

Statewide Spatial Averages

Data from the Delaware Environmental Observing System (DEOS) show that winter temperatures across the entire State were above normal, with the largest anomalies found in northern Sussex and northern New Castle counties in Delaware and in Chester County, PA (Figure 3).

Winter precipitation totals were significantly below normal across the entire State, with the driest conditions along the Sussex County coast (Figure 4). At the New Castle County Airport, only 5.6 inches of snow fell during the December through February winter season, a value far below the 1981-2010 mean of 17.7 inches. During March, another 3.4” of snow fell in northern Delaware bringing the total for the entire snow season (November through April) to 9.0 inches.

Figure 3. Winter 2016 - 2017 average temperature departures (oF) from the 1981-2010 mean based upon DEOS station data.